1. Field of the Invention
This invention relates, generally, to surgical tools. More particularly, it relates to small diameter laparoscopic surgical tools.
2. Description of the Prior Art
FIG. 1 depicts conventional laparoscopic surgery tool 10 having stationary handle 12 connected to sheath 14. Control rod or wire 16 is slideably disposed within a lumen of sheath 14 and its proximal end is connected to actuating handle 18 that is pivotally connected to stationary handle 12. Control rod or wire 16 is pushed or pulled within the lumen so that it extends or retracts relative to a distal free end of sheath 14 in response to manipulation of handle 18 by a surgeon.
Tip mechanism 20 is connected to the distal free end of sheath 14 as best depicted in 2. Tip 20 includes pivotally mounted opposed jaws 20a, 20b that are depicted in their open configuration in FIG. 2 and in their closed configuration in FIG. 1. Jaws 20a, 20b are opened and closed by the extension and retraction, respectively, of control rod or wire 16 to enable tasks such as pinching, cutting, clamping, spreading, suturing, and the like.
Tools such as tool 10 typically have a sheath diameter of five millimeters (5 mm) or more. Conventional laparoscopic surgical technology therefore requires an incision in a patient's abdominal wall that can leave a scar and contribute to postoperative pain. Scarring is avoided only if an incision has a length of 1.6 mm or less.
An alternative methodology that avoids scarring and that reduces post-operative pain includes insertion of laparoscopic tools through a single port in the patient's umbilicus. Such undepicted procedures are difficult because the tools must be used in close proximity to one another. In FIG. 3, three (3) laparoscopy tools denoted 22, 23, and 24 are depicted in a triangulation array that is not possible when all of such tools are inserted through the umbilicus.
Smaller-in-diameter laparoscopic tools, one of which is depicted in FIG. 4 and denoted by the reference numeral 10a, have recently been introduced in an effort to reduce the likelihood of scarring. These tools enable tip 20a to be retracted within the lumen of sheath 14. However, the small size of tip 20a limits its utility, i.e., it is not robust because it has limited surface area or limited force capability for many common surgical procedures. Moreover, the smallest diameter tool, having a sheath diameter of 2.5 mm, is still too large to reduce the likelihood of scarring.
Thus there is a need for a robust laparoscopic tool that can perform pinching, cutting, clamping, spreading, suturing, and other such surgical procedures while requiring an abdominal wall incision that does not exceed 1.6 mm so that such tool can be used in a triangulation array of tools.
However, in view of the art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the art how such a small tool could be provided with the required robust structure.